Merle "Dee" Stedman, 24, of Tigard, is suspected in six robberies in the cities, said Detective Sgt. Jim Shumway, a Beaverton police spokesman. He was arrested on robbery charges and lodged in the Washington County Jail.

Police identified Stedman as the suspect in the crimes after a Beaverton robbery Saturday morning.

Shortly before 10:15 a.m. Saturday, Beaverton police responded to an armed robbery at the Cricket Wireless store, located at 14349 SW Allen Blvd. An employee, who was already a victim in the recent robberies, told police a man, dressed in all black and armed with a gun, demanded cash and stole Bluetooth devices. Before leaving, the man struck the employee in her face and forced her into a large box, Shumway said.

A witness reportedly saw the suspect run from the store and get into a vehicle. The witness provided the vehicle's license plate information to police.

Beaverton detectives responded and started investigating, Shumway said. Using the license plate information, investigators found Stena Mae Mejia, 26, of Aloha, driving the vehicle. Shumway said investigators think Mejia, who is Stedman's sister, was the getaway driver during the incident and later arrested her on one count of first-degree robbery. She could face additional charges.

Stena Mejia Beaverton Police Department

Police found evidence in the vehicle related to an Oct. 23 robbery at a Tigard Dutch Bros. Coffee shop. As detectives continued their investigation, they identified multiple locations in Beaverton, Tigard and Hillsboro that they believed were robbed by the same suspect.

Beaverton detectives contacted Tigard and Hillsboro investigators and told them about a possible lead in their robbery cases, Shumway said. Based on interviews and evidence collected, Shumway said, police identified Stedman as the suspect.

Detectives found Stedman and arrested him Sunday evening on robbery charges. Stedman reportedly led investigators to the pellet gun that he used during some of the robberies. The pellet gun, a replica of a 1911 semi-automatic firearm, was hidden in the woods, Shumway said.

Investigators also served a search warrant at Stedman's home and found robbery evidence.

"The success of this investigation was the result of the collaborative efforts of Beaverton, Tigard, and Hillsboro police departments," Shumway said in a news release. "This case is a good example of the collaborative efforts of these three agencies working together to accomplish the goal."

Shumway said detectives think Stedman is behind these robberies:

May 12th, 2012, Cricket Store, 12025 S.W. Allen Blvd. in Beaverton. A robbery with a wrench as a weapon during which cash and Bluetooth devices were stolen.

Oct. 23, Dutch Bros. Coffee, 11746 S.W. Pacific Highway in Tigard. A robbery with a knife during which money, an iPhone and the victim's identification were stolen.

Oct. 27, Black Rock Coffee, 15290 S.W. Pacific Highway in Tigard. A robbery with a knife during which money was stolen.

Nov. 7, Black Rock Coffee, 15290 S.W. Pacific Highway in Tigard. A robbery with a knife during which money was stolen.

Nov. 14, Cricket Store, 101 N.E. 43rd Ave. in Hillsboro. A robbery with a gun during which cash, and a victim's tablet and wallet were stolen.

Nov. 17, Cricket Store, 14349 S.W. Allen Blvd. in Beaverton. A robbery with a gun, during which cash and Bluetooth devices were stolen.